Degreasing apparatus with automatic controls



Oct. 24, 1950 J, F, BLA K 2,527,349

DEGREASING APPARATUS WITH AUTOMATIC CONTROLS Filed Nov. 18, 1944 2 Sheets-Sheet 1 INVENTOR. JOHN F. BLACK BY rum TTORNEYS Oct. 24, 1950 Filed Nov. 18, 1944 DEGREASING APPARATUS WITH AUTOMATIC CONTROLS J. F. BLACK 2 Sheets-Sheet 2 INVENTOR. JOH N. F. BLAC K ATTOQNEYS Patented Get. 24, 1950 UNITED 1 STATES PATENT l OFFICE John F. Black,-Cleveland, Ohio, assignor to-Circo Products Company, Cleveland, Ohio, acorpomim ohm Application November 18, 1944, Serial No. 564,050 a This invention relates broadly to degreasing apparatus and more speciflcally to certain improvements in the mechanism for the control of the temperature, liquid level, .and vapor heightof the solvent employed therein. U

One of the objects of this invention is to provide apparatus for effecting the removal of grease by soaking. the work piece in a liquid solvent, agitation of the work in the solvent, or dissipation of I the grease by the drainage of the condensate of a solvent vapor. v

Another object is to, provide a pair of tanks or reservoirs one of which is designed to; supply the solvent vaporized inthe other-tank and also designed to accommodate the soaking or agitation methods referred to above. I I H .Another object of this invention is to provide a liquid level control mechanism tor the solvent in the vapor tank which is organized. to provide full freedom of manipulation of the work within the tank and optimum capacity of the tank. f

Another objectis to provide a portable degreasing apparatus in whichthe control mecharnism is readily accessible ior purposes oiad justment, cleaning or repair. l A further objectis realized in the efiiciency of operation, the economy otspace and the mobility of the structure. V v) Other objects and advantages more or less ancillary to the foregoing and the manner in which all the various objects are realized will ap-. pear in the following description, which considered in connection with the accompanying drawings, sets forth the preferred embodiment of the invention:

Referring to thedrawings wherein the praferred embodiment of the invention is illus trated:

Fig, l is an elevational view of the apparatus embodying the present invention,

Fig. 2 is a diagrammatic view of the heating element, the electrical circuittherefor and'the' level control mechanism, and

Fig. 3 is a schematic perspective view partially in section illustrating the relation of the partsshowninFigl. v 3 r v Referring first to Fig. l the vessels or tanks A and B are mounted in contiguous relationship, upon a base ID, theopen upper ends thereoi being formed with arolled flange or beadto strengthen the structure and accommodate the snug engagement of a cover plate or cap II. The tankiA is providedto receive a substantial v u e. of fluidic sql en t he ed iq i e soak:

7Qlaims. (Cl. 202-470) 4 1 and/or agitation cleaning methods and also,

used-asareservoir for the solvent fed to the vaporizing tankzB... A wire basket I2 of any suitable-configuration may .beused to hold small parts'in the fluid.-solvent,,the supporting arms orhooks therefor being designed for interchange able assembly in the, solvent vapor tank B. :The tanks A and B are formed with outlets l3, adjacent the bottom thereof, each having a T M mounted thereon, provided with drain plugs l5 and a conduit 16 uniting the tanks in fluid communication. A T .I'I interposed in said contank B consonant with action of the float and of the action of the solenoid valve 20 in the conduit [6; The conduit [6 is provided with a filter 2| forthe removal from the solvent of any foreign matter which might interfere with the proper operation of solenoid valve 20, a plug valve 22 ,being associated therewith to facilitate the cleaning or renewal thereof.

A heating element 23 is disposed adjacent to and in parallel relation with the bottom of the vapor tank B, the valve 20 being designed to maintain the solvent liquid level in the vapor tank B abov the upper surface of the heating element. A thermostat 24 is mounted in the tank B below the fluid level of the solvent, the thermostat being adjusted to open and close the circuit of said heating element within thermal limits which will maintain adequate vaporization of the solvent for carrying out the degreasingoperation, but below the decomposition temperature of the solvent. A second thermostat 25 is mounted within the vapor tank B in suitably spaced relation with the upper edge thereof to prevent undue. loss of the solvent vapors; generated therein. The solvent vapor, which is several times heavier than air, rises gradually, as vaporization takes place until it envelops and heats the upper thermostat 25. This thermostat is adjusted to open the circuit of the heating element 23 when enveloped by the vapor, and to close the circuit of heating element coincident the fall of the vapor level.

As shown in Fig. 3 the level control switch [9 comprises a three contact mercury switch 23 pendulously supported on a pin 3| by bracket 32 which also supports a magnet 33 in fixed relation with said mercury switch. The solvent level in vapor tank B is effected through the fluid communication of the tank B with the float chamber 18 and the action of a float 34 upon a push rod 35 having a ferrous metal tip 36 thereon for attracting the magnet 33-; As the liquidlevel rises, the float elevates the rod 35 and the metal tip 36 thereon enters the magnetic field of the magnet 33, the attractive force therebetween causing the magnet 33 and the mercury -cup'29 'to swing about its fulcrum 3|.

tion the contacts 26 and 21 are bridged by the mercury and the heater relay circuit is closed. As the liquid level in vaportank B falls the float 34 effects the retraction of the tip 36 from the field of magnet 33. switch 29 will rock, under the influence of gravity, to'its former-position, and: thus close the contacts 26- and 28 :in the circuit of solenoid valve Zll and open the circuit'of the heater relay 30. From the foregoing it will 'be readily recognized that the level control l9 functions to maintain an adequate supply ofliquidsolvent invapor tank B and will protect the heating element 23' from overheating in 'case the solvent level in the vapor tank becomes too' low as a result of an insufficient flow of solvent from the reservoir tank A.

When the mercury cup is biased to the limit of its actuated posi-- Thereupon the 'mercury I he float chamber 18 isprovided with a vent pipe 39, and the open endthereof'is .disposed above the level of the solvent in the reservoir tank A to prevent any overflow if-the solenoid valve should fail to close.

Referring to Fig. 2 it will beseen that the thermostats 24 and 25, and the contacts 26 -and2l in the mercury switch 29 are in'series with the coil winding of the heater relay 30 so that the-circuit to the heater 23 will be closed when and only when the liquid solvent level inthe tank B is adequate; the temperature ofthe liquid solvent is below the decomposition point thereof; and the level of the solvent vapor in'the tank Bis below the gauging level Vof the thermostat 25.

In order to preventarcing" and consequent pitting of the contact pointsa condenser 31 ismstalled in parallel withfthe contacts of thermostats Zd and'25f I v a The apparatus embodying the present invention may be used with facility in continuous operation, or in intermittent serviceof indeterminate time lapse since the automatic control employed therein will safeguard the heating element and maintain the temperature of the'solvent' for immediate use over a considerable period of time without undue loss thereof; b

In use of the apparatus for the removal of heavy coatings of grease from'parts such as the differential gears from a rear axle, the work pieces are first placed in the cold liquidsolvent in the reservoir tank A. When the major portion of the grease is dissolved and/or dislocated by agitation the parts are placed in the vapor bath in tank B. Small parts, hand tools and similar objects, may be suspended in Wire'basket l2 while larger objects may-be placedon the wire grille 38 which serves to protect the heating element and lower thermostat; v

'As the hot solvent vapors contact the cold metal surfaces the -condensate, which though drawn from the grease contaminated solvent in the tank A, is substantially free from grease and oil, dissolves the last vestiges ofgrease remaining after the liquid solvent bath. When it is desired to proceed immediately from the liquid to the vapor bath, the liquid bath should be relatively cool so that the parts introduced into the vapor will effectuate sufiicient condensation of solvent vapor to enliven the drainage thereof. In practice it has beenfound/that the removal of extremely heavy coatings of grease may be expeditiously and efiiciently carried out as heretofore described with the liquid solvent bath at room temperature.

Although the foregoing description is necessarily of a detailed character in order that the invention may be completely set forth, it is to be understood that the specific terminology is not intended'to be restrictive or confining, and that various rearrangements of parts and modifications of detail may be resorted to without departing from the scope or spirit of the invention as herein claimed.

Lclaim: w

1. A degreaser comprising a vaporizing tank, a solvent reservoir, a conduit connecting the reservoir and tank for flow of solventfromthe reservoir to the tank, anormally-closed valve in the conduit, float means responsive to solvent level in the a switch actuated by the float means, a heater for the tank, means actuated by the switch for opening the valve when the solvent level is reduced to a predetermined value, and means operated by the-*switch to de-energize the heater when the solvent level is reduced to-a predetermined value. I V 1 -2. A degreaser comprisinga vaporizing tank, a solvent reservoir, a conduit connecting the reser-' voir and tank for flow of solvent from the-reser voir to the tank, a normally-closed -solenoid valve in theconduit, float means responsive 'to solvent level in the tank, a heater for the tank, a first switch actuated by the responsive means for energizing the solenoid to open the valve when the solvent level is reduced to a predetermined va1ue;-a second-switch operated by the responsive means, and a circuit for the heater energized'by the'second-switch when'the'solvent level is raised above the predetermined Value.

3; A degreasercomprising a vaporizing tank, a heater for the'tank, a first-means responsive to level of the liquid solvent'in'the'tank and actuated'when the level is-reduced to a predetermined value, a second means responsive to temperature of the liquid. solvent in thetank and actuated when the temperature increases to a predetermined value, a third means responsive to'the'level of thevaporized'solvent in-the tankand'actuated when the level increases to ,a'predetermined value, and a fourth-means responsive to actuation of anyone of said' first three-means to deenergize the heater. 7 V I '4. A degreasercomprising a vaporizing tank; a heater for the tank, a float switch responsive to level of theliquid solventin'the'tank'and opened when the level is reduced to'a predetermined value, a thermostaticswitch responsive to tem'- perature of the liquid solvent in the-tank and opened when the'temperature-increases'to-a predetermined value, a thermostatic switch responsive to the level ofthe vaporized solvent in the tank and opened when the level increases'to' a predetermined value, means energized through the three said switches, and-means for energizing the heater actuatedby the first-named means.

- 5. A- degreasing apparatuscomprising a-s'olvent reservoir, a vaporizingtank disposed in-contigu ous relation therewith," a conduit'connecting said reservoir and said tank in fluid communication with each other, a valve in said conduit for restoring the fluid level of the solvent in said vaporizing tank, a solenoid on said valve for the actuation thereof, a submersion type heating element in said vaporizing tank, a float responsive to the fluid level in said tank, a switch actuated by the float, a circuit energized by the switch for opening said valve when the float descends past a predetermined level, and an energizin circuit for said heating element de-energized by said switch for opening said valve when the float descends past a predetermined level.

5. A degreasing apparatus comprising a solvent reservoir tank and a vaporizing tank disposed in contiguous relation, a conduit establishing fluid communication between said tanks, a solenoid valve in said conduit for regulating the flow of solvent from said reservoir tank, a heating element adjacent the bottom of said vaporizing tank, a thermostat disposed in said vaporizing tank and electrically connected to said heating element for controlling the temperature of solvent in the vaporizing tank, a second thermostat in the vaporizing tank having electrical means associated therewith and with said heating element for limiting the height of vapor generated, a float responsive to solvent level in said tank, means actuated by said float for energizing said solenoid valve to open same when th float descends below the predetermined level, and means actuated by said float for de-energizing the heating element when the valve is opened.

7. A degreasing apparatus comprising a solvent reservoir tank and a vaporizing tank in contiguous relation, a conduit connecting said tanks in fluid communication, a valve in said conduit for regulating the flow of solvent therethrough, a float-actuated switch for control of said valve, a heating element in said vaporizing tank; a thermostat in said vaporizing tank to prevent overheatin of the solvent therein, a second thermostat in said vaporizing tank for limiting the height of solvent vapors generated therein, and means actuated by said thermostats and said switch for de-energizing said heating element Whenever either of said thermostats reaches its respective predetermined operating temperature and when said switch is actuated to open said valve.

JOHN F. BLACK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

